1. Field of the Invention
The present invention relates to a manually operated tool designed for use to create grooves in sheets of flooring to receive melted adhesive welding material therein, and grooving blades having a unique configuration and designed for use in such floor grooving tools.
2. Description of the Prior Art
At present, sheets of homogeneous, elastic, PVC, solid vinyl, linoleum, or other rubberized, plastic, or similar flooring are provided in large rolls which can be unrolled at the job site. Such sheets of flooring are typically utilized in hospitals, particularly in surgical areas, as well as in floors of other types of rooms. Such sheets are also used in other types of public buildings, including industrial and commercial buildings. This type of flooring is sometimes used in residential building construction. Smaller sheets in the form of large tiles, one meter square, are also utilized in the same types of applications.
While in some cases the width of the sheets of the flooring are at least as great as one dimension of the room of the floor to be covered, this is often not the case. In such situations the floor covering can be completed only by positioning and butting together two or more sheets of flooring at their edges.
The flooring sheets are secured to the floor by an adhesive compound. To secure the flooring sheets the compound is applied to the floor and the cut sheets of flooring are laid in position, one by one. Once each sheet of flooring is laid, the next adjacent flooring sheet is brought into position and pressed against the floor with the linear edges of adjacent flooring sheets residing in mutual lateral abutment.
One major problem with laying sheets of flooring in this manner is that the adhesive bond between the underside of the flooring sheets and the subfloor beneath is sometimes inadequate. Quite often areas of the sheets of the flooring will tend to separate from the subfloor when the adhesive bond between the subfloor and the flooring sheets deteriorates due to age, movement of the subfloor, or improper installation.
The separation of areas of flooring sheets from the subfloor is particularly pronounced at the interfaces between adjacent sheets of flooring. The edges of adjacent sheets of flooring which are supposed to reside in firm, mutual abutment, will sometimes tend to rise from the subfloor. This condition presents both a dangerous condition and an unsightly appearance. It also leads to a significant deterioration of the floor because of the separation that occurs when the edges of adjacent sheets of flooring rise. When the edges of sheets of flooring separate from the subfloor in this way, moisture and debris often find their way into the crack that forms between the flooring sheets, thus leading to a further deterioration of the floor. This also creates a condition in which bacteria can thrive, which is highly undesirable in a hospital or kitchen environment.
In the floor installation trade the use of fusible plastics to form a seal between the abutting edges of adjacent sheets of flooring has gained increased popular acceptance. According to one technique the edges of sheets of flooring are not cut perpendicular to the plane of the expanse of the flooring as has historically been the practice. Rather, the edges of the flooring are cut so that adjacent sheets of flooring, when moved into abutting relationship, define an upwardly facing, elongated groove where they meet. A fusible plastic sealant is then laid down in this groove or channel in a molten form and then is allowed to cool. Once the fusible plastic sealant solidifies, it adheres to the abutting edges of the flooring sheets and to the concave or upwardly facing surfaces of the adjacent flooring sheets at the demarcation therebetween.
The fused plastic sealant aids in holding the abutting edges of the adjacent sheets of flooring together and prevents moisture and dirt from entering into the junction between the abutting edges of the flooring sheets. Plastic sealants of this type are colored to blend in with the color of the flooring sheets, in most cases, so that the seams between the adjacent flooring sheets are not readily apparent. The fused plastic sealant thereby serves both as an additional measure of protection of the flooring seams from damage, and also as an aesthetically pleasing manner of concealing seams between adjacent flooring sections.
While cutting of the flooring at an angle to form a groove between adjacent sections of flooring represents one method of creating the groove necessary to receive fusible plastic sealant at seams between flooring sections, other devices exist for creating such grooves as well. There are conventional tools that are utilized to form grooves for receiving plastic sealant at abutting edges between flooring sections. One such tool is sold as the Forbo-Groover, one version of which is illustrated in European Patent No. EP 0 297 684. This tool is a hand-operated device that employs a U-shaped gouge located at or near the rear of the device and guided by a pair of spurs, one located at the forward end of the tool and the other at the rear of the tool. One principal difficulty with this prior, convention tool is that the user is only able to form a groove up to about eighteen centimeters away from a vertical abutment surface, such as a wall or cabinet base. Therefore, the installer is left with a problem in that the final distance of about eighteen centimeters cannot easily be grooved.
A very similar conventional device is sold by Janser, Inc. as the xe2x80x9cWheeled Super Grooverxe2x80x9d. However, this device presents the installer with essentially the same problem. That is, the installer can form a groove only up to about thirteen centimeters from a wall or cabinet. To complete the groove all the way to the vertical surface the installer must utilize a very simple, but imprecise, hand-held grooving blade on a projecting arm. Such a hand-held device offers no guidance and no control over either the depth or straightness of the groove.
Electrically operated grooving machines are also available. For example, Janser, Inc. sells grooving machines of this type as Models TFU 1000 and TFU 600. However, these electrically operated devices are considerably more expensive than hand-operated tools, and can form grooves in flooring only up to about thirty centimeters from the wall or other vertical abutment. Thus, in all cases the installer must finish the job of grooving at the seams with an imprecise, hand-held grooving blade.
The present invention provides a manually operated tool which is very light in weight and which provides the flooring installer with guidance to form a straight groove of uniform depth at a seam between two abutting sections of flooring. However, unlike prior conventional systems, the tool of the present invention can form the groove all the way up to a wall or other vertical abutment surface. Also, in contrast to prior conventional systems, the grooving tool of the present invention provides a guidance system to ensure the formation of a straight, linear groove while providing a uniform depth of grooving along the entire length of the seam, without leaving any portion of the seam ungrooved.
Furthermore, the utilization of the grooving tool of the invention is not limited to linear seams. To the contrary, the groove tool can be utilized to form grooves to create designs of decorative patterns in the surfaces of sheets of flooring. The tool of the invention can be utilized to form grooves in circular or other types of arcs which are then filled in with a plastic welding material to create aesthetically pleasing designs, patterns, and inlay work. Conventional tools in which the tracking member is located some distance from the grooving blade cannot perform this function adequately. No conventional groover, either electrically or manually operated, can operate satisfactorily in such an application. Such conventional tools are neither designed nor recommended to perform this task.
A further object of the invention is to provide a blade for grooving flooring that has a unique configuration and which creates a clean, sharply delineated groove of uniform cross section. Conventional grooving blades are formed as gouges that have a U-shaped cross section and are inclined upwardly and forwardly relative to the direction of movement of the tool. This configuration is one of the reasons that such blades cannot be forced all the way to the edges of the sheets of flooring that abut vertical surfaces, such as walls and cabinets. Rather, because of its upward and forward inclination, the upper leading structure of conventional grooving blades meets the vertical surface before the lower, trailing portion does. The obstruction between the upper portion of the blade and the wall prevents the cutting edge of the blade from progressing all the way to the wall, whereby the groove is terminated prematurely.
By utilizing a blade having the configuration of the present invention, however, the blade is oriented at in inclination upwardly and to the rear relative to the direction of travel. As a consequence, the cutting edge of the blade can be pushed all the way up to the edges of the sheets of floor covering that meet the vertical obstruction. Consequently, the grooving blade of the invention can be operated throughout the entire length of the seam between adjacent flooring sections.
In one broad aspect the invention may be considered to be a floor groover for creating grooves in sheets of flooring comprising a longitudinally aligned elongated body having front and rear ends and defining a handgrip therebetween; a narrow rotatable seam-following guide mounted at the front end of the body for rotation about a forward axis of rotation perpendicular to the alignment of the body; a rotatable groove-following guide that is wider than the seam-following guide mounted at the rear end of the body for rotation about a rear axis of rotation perpendicular to the alignment of the body and parallel to the forward axis of rotation, whereby the alignment of the seam-following and groove-following guides defines a longitudinal plane perpendicular to the axes of rotation; a metal front-end grooving blade secured to the body and projecting downwardly and forwardly at in inclination therefrom at the underside thereof centered on the longitudinal plane and formed in the shape of a concave, upwardly facing scoop having a forwardly directly cutting edge that is located directly behind the forward axis of rotation of the seam-following guide; and a metal rear-end grooving blade projecting rearwardly from the rear end of the body and downwardly and rearwardly at an inclination relative to the body centered on the longitudinal plane and formed in the shape of a concave, upwardly facing scooping having a rearwardly directed cutting edge that is spaced rearwardly from the groove-following guide and beyond the rear end of the body.
In the operation of the tool of the invention the body of the tool is moved forwardly with the seam-following guide traveling along the demarcation between the abutting sections of floor covering. The engagement of the seam-following guide in the demarcation between the abutting sections of flooring ensures a straight, linear groove. Both the seam-following guide and the groove-following guide are preferably formed as annular projections at the centers of front and rear rollers, which have a cylindrical cross-sectional configuration. The rollers provide lateral support to hold the front-end and rear-end grooving blades in an orientation centered on a vertical plane that follows the demarcation between the abutting sections of flooring and which perpendicular to the floor. The rollers also ensure that the depth of the groove is uniform along the length of the seam.
As the front-end grooving blade creates a shallow groove in the flooring having a generally hemispherical cross section at the abutting sections of flooring, the groove-following guide travels in the groove so formed to prevent the grooving blades from twisting to one side or the other relative to the path of travel. At the end of the seam the front end of the body of the tool will meet a vertical obstruction near the ends of the flooring sections forming the seam only a little more than a centimeter away from those ends. At this point the tool is rotated one hundred eighty degrees about a vertical axis so that the rear end faces the direction of forward travel of the tool. Since the metal rear-end grooving blade projects beyond the rear end of the body, it can be pushed forward in the direction of travel the last remaining centimeter to complete the groove. During this last increment of travel, both the seam-following guide and the groove-following guide ride along the groove already formed behind the tool.
The use of the floor grooving tool is not restricted to the formation of grooves in abutting sheets of flooring. It can also be utilized to form decorative designs and patterns by creating grooves in the upper surface of a single sheet of flooring. In this connection the invention may also be considered to be a floor groover for creating grooves in sheets of flooring comprising: a longitudinally extending body having opposing front and rear ends and an intermediate portion providing a handgrip therebetween; a seam follower mounted to the body at the front end thereof for rotation about a forward axis that lies in a plane perpendicular to the longitudinal alignment of the body, and including a narrow, annular, rotatable seam-following guide; a metal front-end grooving blade defining a longitudinally aligned, concave upwardly facing scooping channel and having an open cutting mouth at its forward tip located directly behind the forward axis, and the front-end scooping blade is secured to the body and is oriented in an upwardly and rearwardly inclined disposition from the narrow, rotatable seam-following guide.
To inscribe a groove on the upper surface of a sheet of flooring and within its perimeter, the rear grooving blade and the groove-following guide are temporarily removed from the rear of the tool body. This allows the free movement of the seam-following guide and the front-end grooving blade to travel along guidelines marked on the surface of the flooring. The front-end grooving blade can thereby be utilized to form grooves along a circular pattern, grooves along an elliptical pattern, and other grooves of more complex geometric shapes upon the surface of a sheet of flooring. These grooves are then later filled with molten seam welding material of a different color which hardens and adheres to the flooring surface to provide an aesthetically pleasing pattern or a printed legend on the sheet of flooring.
In still another aspect the invention may be considered to be a floor groover blade for creating grooves in sheets of flooring. The blade is comprised of a nose portion forming a metal scoop having a concave upwardly facing channel with an arcuate, concave upwardly facing cutting edge at its extremity and a longitudinally extending anchoring portion for insertion into a floor grooving tool. The cutting edge preferably has a semicircular shape and the scooping channel has a width of at least about three millimeters and no greater than about five millimeters. Sets of floor grooving blades are typically provided as interchangeable elements for the grooving tool in three, four, and five millimeter grooving channel widths.
The invention may be described with greater clarity and particularity by reference to the accompanying drawings.